1. Field of the Invention
The present invention relates to portable electronic devices and, more particularly, to a system and method for displaying battery status and other parameters of a portable electronic device in a power-off state.
2. Discussion of the Related Art
There are a wide variety of portable electronic devices that are operated by battery power and have some sort of visual display, such as a liquid crystal display (LCD), for displaying information to a user. In addition to substantive or operational information, many portable electronic devices may display certain configuration information, such as operational or control settings. Digital cameras are one example of portable electronic devices that have a display for displaying information (in addition to picture or field-of-view information) to a user. During operation, the camera may display a variety of configuration information to the user, such as the number of pictures in memory, the shutter setting, the remaining battery life, and a variety of other settings which may be of interest to the user.
As is known, this information is displayed when a portable electronic device is in an operational mode. Thus, when the device is powered off, for example, this configuration and other information is not displayable to the user. In fact, when the portable electronic device is in a power-off state, typically no power is applied to the display (to maximize the conservation of power and therefore battery life), and therefore nothing is displayed on the display. Further, many portable electronic devices require undesirably long period of time to cycle through start routines (after the device is turned on). Thus, when users desire to know the expected battery life or other parameters of a device that is currently powered off, there is typically an undesirably long waiting period before that information can be displayed.
In the specific situation of a user desiring to obtain information about battery life when the device is powered down, the start-up cycle typically includes a period of time in which the battery-power status is determined. As is know, this determination typically involves placing a load on the battery and measuring the current and/or voltage response to the load.
Accordingly, there is a desire to provide a portable electronic device with the ability to display this information to a user rapidly, even when in a power-off condition.